Family Dorsal Anal Pectoral Pelvic Species Vertebrae Fin Rays Fin Rays Fin Rays Fin Rays

Transcription

1 184 Clupeiformes Meristic characters in species belonging to the order Clupeiformes whose adults or larvae have been collected in the study area. Families and genera are listed alphabetically. Rarely observed counts in parentheses. Sources: Munroe (2000; 2002a; 2002b). Also see species accounts. Family Dorsal Anal Pectoral Pelvic Species Vertebrae Fin Rays Fin Rays Fin Rays Fin Rays Clupeidae Alosa aestivalis Alosa mediocris Alosa pseudoharengus Alosa sapidissima (14)18 19(21) (18)21 22(25) Brevoortia tyrannus Clupea harengus (16)17 19(22) (15)17 19(21) Dorosoma cepedianum Dorosoma petenense (7)8 Etrumeus teres Harengula jaguana (7)8 Opisthonema oglinum Sardinella aurita Engraulidae Anchoa hepsetus Anchoa mitchilli Engraulis eurystole Note: Three species of engraulids can best be distinguished by the relative positions of their dorsal and anal fins and by anal fin ray counts. These characters are most reliable in larvae >10 mm, juveniles and adults. Dorsal and anal fin origins can be almost opposite each other in adult A. mitchilli.

2 Early Stages of Fishes in the Western North Atlantic Ocean 185 Clupeiformes Synopsis of characters for distinguishing larvae of the Clupeidae. "Dors-Anal" refers to number of myomeres between posterior dorsal and anterior anal fins. This number decreases at transformation in most species, as fin positions shift. Note that this number remains relatively stable through ontogeny in the genus Alosa. Notochord Notochord Total Preanal Predorsal Dors-Anal Pigment Pigment Myomeres Myomeres Myomeres Myomeres Dorsal Tip Ventral Tip Miscellanous Alosa aestivalis No Yes Slim-bodied, small-eyed Alosa mediocris In small larvae Yes Alosa pseudoharengus Yes Yes Deep-bodied, large-eyed Alosa sapidissima to 7 1 No Yes Brevoortia tyrannus , 30 31, 5 to 1 In small larvae Yes High D and A then then fin ray counts Clupea harengus , then 33 to to 4 Varies Yes Late anal fin ray formation Dorosoma cepedianum to 7 1 No No Very high anal fin ray count Dorosoma petenense to 7 1 No No Scattered pigment on caudal peduncle Etrumeus teres , 27 32, 5 to 2 No Yes Early teeth; low then 36 then 26 anal fin ray count Harengula jaguana , 25, 5 to 7 Yes If yes, Low myomere then 27 then 10 forms late count Opisthonema oglinum , 26 27, 8 10 to 5 7 No Yes High anal fin then then ray count Sardinella aurita , 26 27, 7 8 to 5 No Yes then 34 then 18 1 Determined from illustrations; need confirmation Patterns of ventral pigment, posterior to cleithrum, in larvae of four species of Alosa. These patterns may be incomplete in many larvae. (Walsh et al., 2005, modified from Sismour, 1994.) Walsh et al., (2005) also provide a sizedependent key to larvae of these four species (plus Dorosoma cepedianum) from the southern part of the study area (Roanoke River, North Carolina). A. pseudoharengus A. aestivalis A. mediocris A. sapidissima

3 186 Alosa aestivalis (Mitchill, 1815) Clupeidae Blueback herring Range: Habitat: Atlantic coast of North America from Nova Scotia to St. John's River, Florida Pelagic, schooling species, inhabiting coastal areas over the inner continental shelf (deeper during winter), moving into brackish or fresh waters to spawn Spawning: Adults migrate into coastal rivers during spring for spawning; begins in late Apr, continues through May in southern part of range, as late as Sep in Connecticut Eggs: Pelagic to semi-demersal, slightly adhesive Diameter: mm Chorion: yellowish, semitransparent Chorion; somewhat thick, inner surface corrugated Oil globules small, unequal in size, scattered Yolk: granular Perivitelline space: wide Meristic Characters Myomeres: Vertebrae: Dorsal fin rays: Anal fin rays: Pectoral fin rays: Pelvic fin rays: 9 11 Caudal fin rays: Yolk-sac larva Larvae: Note: Hatching occurs at mmtl; eye pigmented Body elongate with long, straight gut; anus always posterior to dorsal fin Sequence of fin ray formation: D C A, P 1, P 2 (ossification sequence based on illustrations) myomeres between posterior dorsal and anterior anal fins Discrete melanophores below pectoral fin base become a double line of pigment Pigment along upper and lower gut in distinct rows Notochord tip pigment present on ventral side only Transformation occurs between 20 and 30 mm 1. Slimmer and smaller-eyed than A. pseudoharengus 2. See comparative table in Clupeidae Introduction Early Juvenile: E mmtl Figures: Adult: H.L. Todd (Hildebrand, 1963a); Egg and yolk-sac larva: Mansueti and Hardy, 1967; A B: Chambers et al., 1976; C: Ann S. Green (Hildebrand, 1963a; D: Nancy D. Patton (Hildebrand, 1963a); E: Mansueti and Hardy, 1967 References: Jones et al., 1978; Able and Fahay, 1998; Munroe, 2000; 2002b

4 Early Stages of Fishes in the Western North Atlantic Ocean 187 Alosa aestivalis A mmtl B mmtl C mmtl D mmtl

5 188 Alosa mediocris (Mitchill, 1814) Clupeidae Hickory shad Range: Habitat: Atlantic coast of North America from Bay of Fundy to Florida Inner continental shelf, estuaries, tidal rivers; oceanic distribution during winter not well known Spawning: In tidal freshwater, late Apr through early Jun Eggs: Larvae: Note: Early Juvenile: Spherical, semi-demersal, slightly adhesive Diameter: mm Chorion: transparent, thick, finely corrugated Yolk: densely segmented, amber Oil globules: few, small Perivitelline space: very wide Hatching occurs at mm; eye pigmented Body elongate with long, straight gut; anus always posterior to dorsal fin Preanus length 80 86% TL Posterior gut with muscle-band striations Flexion occurs at mm Yolk-sac larva Sequence of fin ray formation: D C, A, P 2 P 1 (ossification sequence based on illustrations) Pigmentation includes elongate melanophores along ventral surface of gut with few spots on dorsal surface in early larvae; later larvae have melanophores on ventrum from throat area to region above anal fin Transformation occurs between 20 and 30 mm 1. See comparative table in Clupeidae Introduction Meristic Characters Myomeres: Vertebrae: Dorsal fin rays: Anal fin rays: Pectoral fin rays: Pelvic fin rays: 9 Caudal fin rays: E mmtl Figures: Adult: H.L. Todd (Hildebrand, 1963a); Egg, yolk-sac larva and A E: Mansueti, 1962 References: Jones et al. 1978; Able and Fahay, 1998; Munroe, 2000; 2002b

6 Early Stages of Fishes in the Western North Atlantic Ocean 189 Alosa mediocris A mmtl B mmtl C mmtl D mmtl

7 190 Alosa pseudoharengus (Wilson, 1811) Clupeidae Alewife Range: Habitat: Spawning: Eggs: Larvae: Note: Atlantic coast of North America from Newfoundland to South Carolina, most abundant between Gulf of Maine and Chesapeake Bay; also landlocked populations, Great Lakes and New York Pelagic, schooling species, inhabiting coastal areas adjacent to freshwater nursery areas; spends fall and winter in continental shelf waters m deep, primarily off Southern New England, Georges Bank and Gulf of Maine Adults migrate into coastal rivers during spring for spawning; larvae and juveniles occur in estuaries throughout range, except those with limited freshwater input. Demersal and adhesive Diameter: mm Chorion: semitransparent and yellowish Yolk: segmented Oil globules: small, unequal in size, scattered Perivitelline space: wide Hatching occurs at mm; eyes pigmented Yolk-sac larva Body elongate with long, straight gut; anus always posterior to dorsal fin Preanus length about 80% TL Posterior gut with muscle-band striations at sizes >10.0 mm Flexion occurs at about 9.0 mmsl Sequence of fin ray formation: D, C A P 2 P 1 (ossification sequence based on illustrations) Pigmentation includes row of spots on dorsal half of anterior gut, ventral surfaces of posterior gut; early larvae have rows of spots on dorsal and ventral surfaces of caudal peduncle; 1 large melanophore above base of pectoral fin; dorsolateral pigment appears in larger larvae Transformation occurs between 25 and 30 mm 1. Deeper-bodied and larger-eyed than Alosa aestivalis 2. See comparative table in Clupeidae Introduction Early Juvenile: Larger juveniles have single, dark spot on side posterior to opercle Sharp scutes form along midline of belly Meristic Characters Myomeres: Vertebrae: Dorsal fin rays: Anal fin rays: Pectoral fin rays: Pelvic fin rays: 9 10 Caudal fin rays: 10+9 (PrC) E mmtl Figures: Adult: H.L. Todd (Hildebrand, 1963a); Egg, yolk-sac larva: Mansueti and Hardy, 1967; A B: Chambers et al., 1976; C: Norden, 1967; D: Ann S. Green (Hildebrand, 1963); E: Mansueti and Hardy, 1967 References: Jones et al., 1978; Able and Fahay, 1998; Munroe, 2000; 2002b

8 Early Stages of Fishes in the Western North Atlantic Ocean 191 Alosa pseudoharengus A. 9.0 mmtl B mmtl C mmtl D mmtl

9 192 Alosa sapidissima (Wilson, 1811) Clupeidae American shad Range: Habitat: Atlantic coast of North America from Labrador to Florida; most abundant between Connecticut and North Carolina Congregate in Gulf of Maine during summer and fall, then most overwinter off Middle Atlantic Bight, at depths to 230 m Spawning: Adults migrate into coastal rivers to spawn during spring; larvae develop in freshwater, juveniles form schools as they drift downstream summer and fall Eggs: Larvae: Demersal, adhesive early stages Later stages non-adhesive Diameter: mm Chorion: Transparent, pale pink or amber Yolk: segmented Oil globules: none Perivitelline space: wide Yolk-sac Larva Hatching occurs at mm Body elongate with long, straight gut; anus always posterior to dorsal fin Air bladder obvious by 14 mm TL Preanal finfold retained throughout larval development Sequence of fin ray formation: D, C A P 2 P 1 (ossification sequence based on illustrations) Transformation occurs between 25 and 30 mm Note: 1. See comparative table in Clupeidae Introduction Early Juvenile: 2. Ventral pigment in small A. sapidissima (center) differs from that in A. aestivalis (left) and A. pseudoharengus (right) in sizes <13.0 mmtl (after Sismour, 1994) Meristic Characters Myomeres: Vertebrae: Dorsal fin rays: Anal fin rays: Pectoral fin rays: Pelvic fin rays: 8 10 Caudal fin rays: 10+9 (PrC) E mmtl Figures: Adult: H.L. Todd (Hildebrand, 1963a); Egg, yolk-sac larva and A: Ryder, 1887; B E: Mansueti and Hardy, 1967 References: Jones et al., 1978; Able and Fahay, 1998; Munroe, 2000; 2002b

10 Early Stages of Fishes in the Western North Atlantic Ocean 193 Alosa sapidissima A mmtl B mmtl C mmtl D mmtl

11 194 Brevoortia tyrannus (Latrobe, 1802) Clupeidae Atlantic menhaden Range: Habitat: Atlantic coast of North America from the Gulf of St. Lawrence to northern Florida Pelagic, brackish estuaries and bays as well as inner continental shelf; rarely far from land Spawning: May spawn during every month of the year, depending on location, with peaks during spring and fall; in the study area, most larvae occur in the Middle Atlantic Bight during fall into winter, with more limited occurrences in coastal waters during spring Eggs: Larvae: Note: Pelagic, spherical Diameter: mm Chorion: smooth and thin Yolk: segmented Oil globules: single, mm in diameter Perivitelline space: wide Late embryo has 2 rows of dorsolateral spots from snout to tail Hatching occurs at mm; eyes unpigmented Body elongate, with straight gut 70 80% TL; anus always posterior to dorsal fin Flexion occurs at 8 10 mm Posterior gut has obvious muscle-band striations Air bladder evident at about 11 mm No teeth until 20 mm Sequence of fin ray formation: C, D, A P 2 P 1 Pigmentation includes spots along entire dorsal surface of gut and along ventral surface of posterior half of gut in larvae larger than about 5 mm; few melanophores along dorsum of body disappear at 5 6 mm; pigment present on ventral side of notochord tip; dorsal notochord tip pigment only present in small larvae When spawned offshore, larvae enter estuaries after about 1 month at sizes of 10+ mm Transformation occurs at about 30 mm (in estuaries) 1. High number of dorsal and anal rays compared to other clupeids 2. Myomeres between posterior dorsal and anterior anal fins decrease from 5 to 1 Meristic Characters Myomeres: Vertebrae: Dorsal fin rays: Anal fin rays: Pectoral fin rays: Pelvic fin rays: 7 Caudal fin rays: Yolk-sac larva 3. Brevoortia smithi occurs only as far north as Cape Hatteras; myomeres; transforms at mm Early juvenile: F mm Figures: Adult: Whitehead, 1977; Egg and yolk-sac larva: Kuntz and Radcliffe, 1917 (redrawn); A D: Mansueti and Hardy, 1967 (redrawn); E F: Lewis et al., 1972 References: Houde and Swanson, 1975; Ditty et al. 1994; Munroe, 2000; 2002b

12 Early Stages of Fishes in the Western North Atlantic Ocean 195 Brevoortia tyrannus A. 8.3 mmtl B mmtl C mmtl D mmtl E mmtl

13 196 Clupea harengus Linnaeus, 1758 Clupeidae Atlantic herring Range: Habitat: Both sides of North Atlantic Ocean; in the western North Atlantic from Greenland and Labrador to Cape Hatteras; separate stocks occur in Gulf of St. Lawrence, Banquereau Bank, Scotian Shelf, Gulf of Maine and Georges Bank Pelagic, schooling; mostly offshore and migrating into deeper waters during winter; some populations move into coastal waters for spawning Spawning: Mostly in fall, with a peak in Sep; also a spring spawn, peaking in May; occurs in bays and offshore banks, usually over substrates of rock, cobble or gravel. Georges Bank and periphery of Gulf of Maine are important centers; larvae seldom occur south of Hudson Canyon or off Nw Jersey Meristic Characters Myomeres: Vertebrae: Dorsal fin rays: Anal fin rays: Pectoral fin rays: Pelvic fin rays: 6 10 Caudal fin rays: Eggs: Demersal, adhesive, clumping, off-round Diameter: mm Chorion: smooth, transparent and thick Yolk: segmented Oil globules: none Perivitelline space: wide Yolk-sac larva Larvae: Note: Hatching occurs at 4 10 mmtl; eyes pigmented Body elongate with long straight gut; anus always posterior to dorsal fin Preanus length 80%TL Flexion occurs at mm Posterior gut has obvious muscle-band striations Air bladder forms at 5 10 mm, but not obvious until 30 mm Sequence of fin ray formation: C D, A P 2 P 1 Pigmentation includes melanophores along the dorsal surface of the gut anteriorly, ventral surface of the gut posteriorly; larger larvae have only dorsal gut pigment; early larvae have single streak of pigment on midline of isthmus; large melanophores occur near anus, and at base of caudal fin; pigment present on ventral surface of notochord tip, variable on dorsal surface Transformation occurs at about 30 mm 1. High myomere count and late forming anal fin rays are unique for North Atlantic clupeids Early Juvenile: 2. Myomeres between posterior dorsal and anterior anal fins decrease from 8 9 to 4 3. See Mallotus villosus for note on similar larva F mmsl Figures: References: Adult: Hildebrand, 1963a; Eggs: Berg et al., 1949; Yolk-sac larva, A B, D: Krevanovsky, 1956 (redrawn); C: Ehrenbaum, 1909 (redrawn); E: Fage, 1920 (redrawn); F: Susan Kaiser (Able and Fahay, 1998) Russell, 1976; Jones et al., 1978; Able and Fahay, 1998; Munroe, 2000; 2002b

14 Early Stages of Fishes in the Western North Atlantic Ocean 197 Clupea harengus A. 8.2 mmtl B mmtl C mmtl Pigment increases on head and dorso-lateral region D mmtl (Head Region) E mmtl

15 198 Dorosoma cepedianum (Lesueur, 1818) Clupeidae Gizzard shad Range: Habitat: Spawning: Eggs: Larvae: Early Juvenile: North American fresh water drainages into the Atlantic Ocean and Gulf of Mexico; reaches estuarine waters of Chesapeake and Delaware bays and as far north as Hudson River estuary Near surface in open, quiet waters, deeper in fall and winter; found in submerged vegetation and over mud, sand and gravel substrates In fresh water in sloughs, ponds, lakes and larger rivers; spring through summer, with peak Apr Jun Demersal, adhesive Diameter: 0.75 mm Chorion: smooth, tough Yolk: finely granular Oil globule: 1 large and 1 5 smaller ones Perivitelline space: narrow Hatching occurs at about 3.2 mm Body elongate with long straight gut; anus always posterior to dorsal fin Remnant of preanal finfold still present at 17 mm Flexion occurs between 11 and 17 mm Sequence of fin ray formation: D C A, P 2 P 1 Pigmentation includes large melanophores near anus, and a series of spots on dorsal surface of anterior gut; larger larvae develop scattered pigment on caudal fin along base of anal fin, and dorsolaterally on body Transformation occurs at sizes larger than 24 mm; body begins to deepen at about 35 mm Scales complete at about 50 mm Large melanophore forms behind opercle in juveniles Ventral scutes form at about 35 mm Note high anal fin ray count Meristic Characters Myomeres: Vertebrae: Dorsal fin rays: Anal fin rays: Pectoral fin rays: Pelvic fin rays: 7 10 Caudal fin rays: Yolk-sac larva F mmtl Figures: Adult: H.L. Todd (Goode, 1884); Egg, yolk-sac larva, and B C: Warner, 1940; A, D: Lippson and Moran, 1974; E: Fowler, 1935; F: Fowler, 1945 References: Lippson and Moran, 1974; Jones et al., 1978

16 Early Stages of Fishes in the Western North Atlantic Ocean 199 Dorosoma cepedianum A mmtl B mmtl C mmtl D mmtl E. 35 mmtl

17 200 Dorosoma petenense (Günther, 1867) Clupeidae Threadfin shad Range: Habitat: Ohio River drainage of North America to fresh waters of northern Guatemala and Belize; introduced into Chesapeake Bay drainages and occurs in Chesapeake and Delaware Canal Pelagic, schooling, in large bays, lakes, reservoirs, estuaries; in salinities 0 32 ppt, but mostly below 5 ppt Spawning: Eggs and larvae may be restricted to fresh water, although juveniles and adults are occasionally collected in estuarine conditions Eggs: Demersal, adhesive Diameter: 0.75 mm No other data Meristic Characters Myomeres: Vertebrae: Dorsal fin rays: Anal fin rays: Pectoral fin rays: Pelvic fin rays: (7) 8 Caudal fin rays: 10+9 (PrC) Larvae: Hatching occurs at mm Body elongate with long, straight gut; anus always posterior to dorsal fin Flexion occurs at about 10 mmtl Yolk-sac larva About 36 preanal myomeres Sequence of fin ray formation: C, D A P 2 P 1 (ossification sequence based on illustrations) Adult fin ray complement present by mm Pigmentation includes a series of melanophores on dorsal surface of anterior gut, and scattered pigment over the anal fin base and caudal peduncle Transformation begins at about 20 mm Figures: Adult: Miller, 1963; Yolk-sac larva and A E: Taber, 1969 References: Lippson and Moran, 1974; Jones et al., 1978

18 Early Stages of Fishes in the Western North Atlantic Ocean 201 Dorosoma petenense A. 8.2 mmtl B mmtl C mmtl D mmtl E mmtl

19 202 Etrumeus teres (DeKay, 1842) Clupeidae Round herring Range: Habitat: Western North Atlantic Ocean from Bay of Fundy to Florida and Gulf of Mexico; also eastern Pacific and Indo-Pacific oceans Pelagic, schooling in continental shelf waters; occasionally in bays and coastal waters, but mostly over outer continental shelf depths Spawning: Not well-described; possibly restricted to south of Cape Hatteras and Gulf of Mexico; larvae occasionally collected in study area Eggs: Larvae: Note: Early Juvenile: Pelagic, spherical Diameter: mm Chorion: smooth, transparent and thick Yolk: segmented Oil globules: none Perivitelline space: narrow Hatching occurs at mm; eyes unpigmented Body elongate with long, straight gut; anus always posterior to dorsal fin Yolk-sac Larva Teeth apparent at about 6 mmtl Snout long and pointed in small larvae Flexion occurs at 8 10 mmsl Posterior gut has obvious muscle-band striations Sequence of fin ray formation: C, D A P 2 P 1 Fin rays not complete until transformation; pelvic forms late and migrates posteriorly Pigmentation includes about 8 widely spaced, large spots over anterior gut; small spots in double row form over posterior gut; a large melanophore over anus; spot at tip of lower jaw in some larvae Diagonal streaks of pigment over lower caudal fin base are distinctive Transformation occurs at mmtl 1. Early teeth formation and low anal fin ray count are unique among clupeid larvae 2. Myomeres between posterior dorsal and anterior anal fins decrease from 5 to 2 Meristic Characters Myomeres: Vertebrae: Dorsal fin rays: Anal fin rays: Pectoral fin rays: Pelvic fin rays: 8 Caudal fin rays: F mmtl Figures: References: Adult: Whitehead, 1977; Egg: O'Toole and King, 1974; Yolk-sac larva: Mito, 1961a; A: Mito, 1961; B: Houde and Fore, 1973; C: Uchida et al. 1958; D: Nancy Arthur (Moser et al. 1996); E F: Hildebrand, 1963a (Yolk-sac larva and A C redrawn) E.D. Houde, 1981 (pers. comm.); Shaw and Drullinger, 1990; Munroe, 2000; 2002b

20 Early Stages of Fishes in the Western North Atlantic Ocean 203 Etrumeus teres A. 5.7 mmtl B. 8.5 mmtl C mmtl Eye oval in early stages, becomes round at transformation D mmtl E mmtl

21 204 Harengula jaguana Poey, 1865 Clupeidae Scaled sardine Range: Habitat: Western North Atlantic Ocean from New Jersey to southern Brazil, including Gulf of Mexico and Caribbean Sea Pelagic and demersal in coastal waters, over mud or sand substrates; often in bays, estuaries or high salinity lagoons Spawning: Jan Sep (peak Apr Aug); most activity over inner continental shelf at night Eggs: Pelagic, spherical Diameter: mm Chorion: transparent Yolk: segmented Oil globule: single, mm in diameter Perivitelline space: wide Meristic Characters Myomeres: Vertebrae: Dorsal fin rays: (19) Anal fin rays: Pectoral fin rays: (13) Pelvic fin rays: (7) 8 Caudal fin rays: Larvae: Hatch at about 2.5 mmtl, eyes unpigmented, mouth parts unformed Body elongate, with straight gut 85 90% TL (decreases to 75% at transformation) Anus always posterior to dorsal fin Preanus myomeres 35 at 6.0 mm, 27 at 22 mm Predorsal myomeres 25 at 6.0 mm, 10 at 22 mm Flexion occurs at 9 11 mm Posterior gut has obvious muscle-band striations Air bladder evident at 6.0 mm Sequence of fin ray formation: C, D A P 2 P 1 Dorsal fin rays complete at mm; anal fin rays complete at mm Pigment sparse on head; early larvae have spots on dorsal (and ventral) tip of notochord, spots at cleithral symphysis, 2 spots near anus, ventral row of spots along posterior gut plus row of spots along dorsum of anterior gut; later larvae form row of spots along dorsum of posterior gut, few spots on bases of caudal fin rays; largest larvae add short rows of spots under dorsal fin and from posterior anal fin on venter of caudal peduncle; few spots also on hindbrain and on "cheek" area Transformation occurs at about mm Note: 1. Low total myomere count; myomeres between dorsal and anal fins 5 7 Early Juvenile: F mmsl Figures: Adult: Munroe and Nizinski, 2002; Egg: Gorbunova and Zvyagina, 1975; A, C, E F: Houde et al., 1974 (redrawn); B, D: Ditty et al., 2006 References: Houde et al., 1974; Gorbunova and Zvyagina, 1975; Fahay, 1983; Munroe and Nizinski, 2002

22 Early Stages of Fishes in the Western North Atlantic Ocean 205 Harengula jaguana A. 6.0 mmsl B. 8.6 mmsl C mmsl D mmsl E mmsl

23 206 Opisthonema oglinum (Lesueur, 1817) Clupeidae Atlantic thread herring Range: Habitat: Western North Atlantic Ocean from southern New England and Bermuda, through the Gulf of Mexico, Caribbean Sea and West Indies; mostly tropical and sub-tropical waters; also eastern Pacific Ocean Pelagic, schooling in coastal waters, usually in high salinity, more rarely in bays or estuaries Spawning: May Jun off North Carolina; larvae rarely collected in study area Eggs: Pelagic, spherical Diameter: mm Chorion: smooth, thin and clear Yolk: lightly segmented Oil globule: single; mm in diameter Perivitelline space: wide Paired dorsolateral series of melanophores on late embryo Meristic Characters Myomeres: Vertebrae: Dorsal fin rays: Anal fin rays: Pectoral fin rays: Pelvic fin rays: 8 9 Caudal fin rays: Larvae: Note: Early Juvenile: Hatching occurs at >3.0 mm; eyes unpigmented Body elongate with long, straight gut; anus always posterior to dorsal fin Preanus length decreases from 86 91% TL before flexion to 75% SL after transformation Predorsal myomeres decrease from 25 to 15 Flexion occurs at about 10 mmsl Posterior gut has obvious muscle-band striations Air bladder present, but not obvious until transformation Sequence of fin ray formation: C D A P 2 P 1 Pigmentation: in early larvae, melanophores on ventral midline under pectoral fins, posterior to anus, a double row along ventral surface of hindgut, and a dorsolateral row on each side of foregut Internal pigment over posterior gut well-defined; internal spots over air bladder prominent Transformation occurs at mmsl 1. Myomeres between posterior dorsal and anterior anal fins decrease from 8 10 (<16 mm) to 5 7 at transformation 2. Notochord tip pigment restricted to ventral side 3. High anal fin ray count 4. Pigment increases on dorsum of head at about 24 mmsl H mmsl Figures: Adult: A.S. Green (Munroe, 2002b); Egg and A H: Richards et al., 1974 References: Richards et al., 1974; Munroe, 2000; 2002b; Munroe and Nizinski, 2002

24 Early Stages of Fishes in the Western North Atlantic Ocean 207 Opisthonema oglinum A. 4.0 mmtl B mmsl C mmsl D mmsl E mmsl F mmsl G mmsl (Dorsal Head)

25 208 Sardinella aurita Valenciennes, 1847 Clupeidae Spanish sardine Range: Habitat: Spawning: Eggs: Larvae: Note: Eastern and western North Atlantic Ocean and Mediterranean Sea; in the western North Atlantic from Cape Cod and Bermuda to Brazil, including Gulf of Mexico and Caribbean Sea Pelagic in inner continental shelf waters Year-round with distinct peaks in different areas; fall winter off Florida; Nov Jun (peak Jan Feb) off Venezuela; mid-jun Sep off North America; Sep Feb in Gulf of Mexico; larvae uncommonly collected in study area during spring Pelagic and spherical Diameter: (1.25) mm Chorion: thin, unsculptured, unpigmented Yolk: vaguely segmented Oil globule: single, mm in diameter Perivitelline space: moderately wide Hatching occurs at 2.5 mm, eyes and body unpigmented, yolk-sac elliptical with oil globule posteriorly Preanal length ranges from 83 89% SL, then decreases to 73% SL at transformation; head length ranges from 14 27% SL, then increases to 29% SL at transformation; body depth ranges from 8 12% SL, then increases to 25% SL at transformation Dorsal fin migrates forward: predorsal length 60 68% SL until transformation when it decreases to 41% SL Myomeres between posterior dorsal fin and anterior anal fin decrease from 7 8 to 5 Flexion occurs at 7.5 to 9.5 mm Sequence of fin ray formation: C D, A P 2 P 1 Pigmentation: melanophores occur on nape, over brain and in area of cleithral symphysis; row of elongate melanophores along dorsal aspect of foregut; increasing number of spots along dorsal aspect of hindgut, fewer spots along ventral aspect of hindgut; other melanophores occur along dorsal fin base and lateral body after 16 mm; a few internal melanophores over the anteriormost vertebrae; pigment at notochord tip usually only ventral; pigment on caudal fin increases in larger larvae Transformation occurs at mm 1. See Clupeidae comparative table on Clupeiformes Introductory page 2. Lower anal fin ray count than in Opisthonema oglinum Meristic Characters Myomeres: Vertebrae: Dorsal fin rays: Anal fin rays: Pectoral fin rays: Pelvic fin rays: 7 8 Caudal fin rays: Early juvenile: In early juveniles, last ray of anal fin is longer than other rays, but last ray of dorsal fin is not elongate; no dark spot on body behind opercle Figures: Adult: Hildebrand, 1963a; A F: Ditty et al., 1994 References: Fage, 1920; Matsuura, 1972, 1975; Houde and Fore, 1973; E. D. Houde, 1981 (pers. comm.); Munroe and Nizinski, 2002

26 Early Stages of Fishes in the Western North Atlantic Ocean 209 Sardinella aurita A. 3.6 mmsl B. 5.5 mmsl C. 8.1 mmsl D mmsl E mmsl F mmsl

27 210 Anchoa hepsetus (Linnaeus, 1758) Engraulidae Striped anchovy Range: Habitat: Atlantic coasts of North America and South America from Nova Scotia to Uruguay; absent from Florida Keys and most of Caribbean Sea Schooling, pelagic, in estuarine and oceanic waters; mostly over inner continental shelf; oceanic occurrences not well-described Spawning: Spring and summer; Apr Sep off NE United States, with peak May Jul; commences near Cape Hatteras, later in southern New England waters; mostly over inner continental shelf; sporadic occurrences until Sep Meristic Characters Myomeres: Vertebrae: Dorsal fin rays: Anal fin rays: Pectoral fin rays: Pelvic fin rays: 7 Caudal fin rays: Eggs: Larvae: Note: Pelagic, elliptical Diameter: long axis mm; short axis mm Chorion: smooth and transparent Yolk: segmented Oil globules: none Perivitelline space: narrow Hatching occurs at mm; yolk mass tapers posteriorly Body long and slender; anus under dorsal fin Mouth large, terminal, extends to under middle of eye; becomes sub-terminal Flexion occurs between 5 and 10 mm - Gut with muscle-band striations posteriorly Sequence of fin ray formation: C, D, A P 2 P 1 Pigment very light; series of melanophores along dorsal surface of gut and along anal fin base 1. Amount of overlap between dorsal and anal fins and number of anal fin rays best characters for distinguishing this species from 2 other engraulid species in study area (see Clupeiformes Introduction) Early Juvenile: E mmtl Figures: Adult: Whitehead et al., 1988; Egg, A B: Hildebrand and Cable, 1930; C: Wayne LaRoche (Farooqi et al., 1995); D: Lippson and Moran, 1974; E: Nancy Arthur (Able and Fahay, 1998) (A, B, D redrawn) References: Able and Fahay, 1998; Berrien and Sibunka, 1999; Munroe, 2000; 2002a; Nizinski and Munroe, 2002

28 Early Stages of Fishes in the Western North Atlantic Ocean 211 Anchoa hepsetus A. 3.6 mmtl B. 5.6 mmtl C mmsl D mmtl

29 212 Anchoa mitchilli (Valenciennes, 1848) Engraulidae Bay anchovy Range: Habitat: Atlantic coast of North America from Maine to Florida, through Gulf of Mexico to Yucatan Peninsula, Mexico Schooling, pelagic; estuarine and coastal ocean; sandy beaches, open bays, muddy coves Spawning: Primarily in water <20 m deep in bays, estuaries, sounds and coastal ocean; begins as early as Apr off Cape Hatteras, expands rapidly northward over inner continental shelf waters during May and June, occurs as far north and east as Long Island to Narragansett Bay, Rhode Island in July; declines between September and October Eggs: Pelagic, slightly elliptical Diameter: long axis: mm Chorion: smooth and transparent Yolk: segmented Oil globules: none Perivitelline space: narrow Meristic Characters Myomeres: Vertebrae: Dorsal fin rays: Anal fin rays: Pectoral fin rays: Pelvic fin rays: 7 Caudal fin rays: Larvae: Note: Early Juvenile: Hatching occurs at mm (smaller than other engraulids); yolk tapers posteriorly Body long and slender, with anus under dorsal fin Mouth large and terminal, extends to middle of eye; becomes sub terminal Flexion occurs at 7 8 mm Gut with muscle band striations posteriorly Sequence of fin ray formation: C, D, A P 2 P 1 Pigment very light, but somewhat more dense than in larvae of 2 other engraulids in study area; series of melanophores along dorsal surface of gut and along anal fin base Transformation occurs at about 20mm 1. Amount of overlap between dorsal and anal fins and number of anal fin rays best characters for distinguishing this species from 2 other engraulid species in study area (see Clupeiformes Introduction) F mmsl Figures: Adult: Whitehead et al. 1988; Egg, A, C: Kuntz, 1915; B: Lippson and Moran, 1974; D: Mansueti and Hardy, 1967; E: Fowler, 1945; F: Susan Kaiser (Able and Fahay, 1998) (A E redrawn) References: E. D. Houde, 1982 (pers. commun.); Vouglitois, et al., 1987; Able and Fahay, 1998; Berrien and Sibunka, 1999; Munroe, 2000; 2002a

30 Early Stages of Fishes in the Western North Atlantic Ocean 213 Anchoa mitchilli A. 1.9 mmtl B. 8.4 mmtl C mmtl D mmtl E mmtl

31 214 Engraulis eurystole (Swain and Meek, 1885) Engraulidae Silver anchovy Range: Habitat: Atlantic coast of North America from Massachusetts to northern Gulf of Mexico; also Venezuela to northern Brazil; larvae occur as far north as Scotian Shelf Schooling, pelagic; mostly over continental shelf waters Spawning: Spring into fall; not well-described; larvae rarely collected in estuaries, or as far offshore as Gulf Stream Eggs: Pelagic, elliptical Diameter: long axis: mm; short axis: mm Chorion: smooth and transparent Yolk: segmented Oil globules: none Perivitelline space: narrow Meristic Characters Myomeres: Vertebrae: =43 45 Dorsal fin rays: Anal fin rays: Pectoral fin rays: Pelvic fin rays: 7 Caudal fin rays:?+10+9+? Larvae: Note: Hatching occurs at 2 3 mm; yolk tapers posteriorly Body long and slender; anus under dorsal fin Mouth large, terminal; extends to middle of eye; becomes subterminal Gut with muscle-band striations posteriorly Air bladder prominent in larger larvae (Fig. D and F) Sequence of fin ray formation: C, D, A P 2 P 1 Pigment very light, increases with development; note ventral series of melanophores along dorsal surface of gut and along anal fin base; row of elongate spots forms along mid isthmus in larger larvae; larvae near transformation develop pigment on head, along lateral midline, on caudal fin rays and on dorsal peritoneum Transformation occurs between 20 and 23 mm 1. Amount of overlap between dorsal and anal fins and number of anal fin rays best characters for distinguishing this species from 2 other engraulid species in study area (see Clupeiformes Introduction) Early Juvenile: F mmsl Figures: Adult: Whitehead et al., 1988; Egg, A C: Kuntz and Radcliffe, 1917; E: Lippson and Moran, 1974; D, F: Markle et al., 1980 (A C, E redrawn) References: Markle et al., 1980; Able and Fahay, 1998; Berrien and Sibunka, 1999; Nizinski and Munroe, 2002

32 Early Stages of Fishes in the Western North Atlantic Ocean 215 Engraulis eurystole A. 3.2 mmtl B. 3.4 mmtl C. 5.2 mmtl D mmsl E mmtl